Headlight Motor question please help

[guitarbare]

THIS IS A 1990 C4 ZR1 whenever I raise or lower the headlamps the drivers side
motor runs on after the it's fully up or down for around 10 secs.. is this normal?
how ro fix?

Larry

 

[seajayiii]

Hey Larry. The answer is no ... the motor should not run on once the lamp is fully up. I recently had this problem with my '90 coupe. Eventually, the headlamp will not fully raise, or will start to slip back into the closed position. The problem is in the headlamp motor. If you search the forums, you'll find many, many threads that will show you in great detail how to replace and repair the headlamp motor. Basically, there are bushings within the headlamp motor that eventually disintegrate. My bet is that's what's going on inside your headlamp motor. Over time, the bushings deteriorate and the motor will not turn the headlamp properly. Most enthusiasts will encourage you to remove the headlamp motor and replace the bushings within the motor. In my case, I needed to fix the problem quickly (had to get the Vette inspected). I purchased a rebuilt headlamp motor from Eckler's (www.ecklers.com). It cost me about $150 with shipping and handling. I removed the headlamp assembly and replaced the old motor with the rebuild. The whole job took about an hour and one half ... including clean up. The motor works beautifully and does not run on after the headlamps are engaged ... and the car passed inspection. Now the other side is starting to make some funny noises. I figured that was gonna happen since both motors were original equipment. This time, I am gonna try rebuilding the motor myself by replacing the bushings since I have time.

Again, search the threads and you'll find PLENTY of help here. Good luck.

 

[onedef92]

You can purchase the O.E.M. Delrin bushings wayyyyyyyyyyyyy cheaper than $150.00 bones.

I'd order them online from Eckler's or MAM (Mid-America Motorworks) for $7.99 plus shipping.

Or, if you don't want to wait, go to AutoZone or another auto parts retailer and ask for Window Regulator Gear Plugs by MotorMite HELP! The Part No. is 74410.

They sell for about $7.95 for a set of 3 bushings. You'll need six to do both lights. They are semi-soft and will absorb the opening and closing shock to the headlight gear better than the bushings you can get from Lowe's or Home Depot.

You can easily replace BOTH bushings in four hours or less if you've done it before. It's a good weekend project. Click this article from Corvette Fever for how-to info! Good luck.

http://www.corvettefever.com/howto/33098/index.html

 

[zrtwooo]

So let me see if i understand... the motor running for about 10 seconds after the light is up or down is becaust of 6 bushings need to be replaced? thats it? I have a couple of spaer motors that dad sent with the car that sounds like i don't need. Please cleify this for me... I'm a bit slow on the uptake..
thx
Mike

 

[Edmond]

Yep, that's it. I know it sounds amazingly simple. To me, they were a PITA to get to. You'll probably need another pair of hands as I did.

Those little bushings are plastic and over the years, they just grind up until it's powder. You'll see that once you take the cover off, a bunch of powder will fall out.

Use this: http://www.corvettefever.com/howto/33098/index.html

That article guided me all the way through.

 

[gmjunkie]

Or, if you don't want to wait, go to AutoZone or another auto parts retailer and ask for Window Regulator Gear Plugs by MotorMite HELP! The Part No. is 74410.

They sell for about $7.95 for a set of 3 bushings. You'll need six to do both lights. They are semi-soft and will absorb the opening and closing shock to the headlight gear better than the bushings you can get from Lowe's or Home Depot.

You can easily replace BOTH bushings in four hours or less if you've done it before. It's a good weekend project.

It takes me about a hour a side by myself,but I've done it at least 100+ times!! Be careful and soak all the bolts and screws with PB Blaster!! If you break one off, then it becomes a Real PITA!!:L:L:L

 

[rascal_rascal_99]

There is another walk through that I'd used, very simple procedure...HERE
or if that didn't link right, the complete url is:
http://mywebpages.comcast.net/zrjuan/headlight.html

Last thread I found where I'd talked about doing mine, is This One

I do mention in there that there is a small pin that has to be removed, I'd had to replace those to put it back together, not sure if every else does too or not. We're still talking about less than 10$ total for six bushings and two retaining pins...I'm thinking they are about an inch long, but can't remember if they were 1/16" or 1/8"...and honestly, if I remember right I only had metric one's handy and used a 3mm, it worked but was a little tight. Hey Junk, what's the correct size for someone that doesn't use the "I've got a big enough hammer, it'll work!" mentality?

If I understand correctly though, why your headlight motors are running longer than needed, it's too free inside and the motor doesn't have enough pressure against it to trigger it off, so it just runs until it times out.

 

[gmjunkie]

I'm thinking they are about an inch long, but can't remember if they were 1/16" or 1/8"...and honestly, if I remember right I only had metric one's handy and used a 3mm, it worked but was a little tight. Hey Junk, what's the correct size for someone that doesn't use the "I've got a big enough hammer, it'll work!" mentality?

If I understand correctly though, why your headlight motors are running longer than needed, it's too free inside and the motor doesn't have enough pressure against it to trigger it off, so it just runs until it times out.

Yep, you have it right,or at least close enough!! I just Mic'd a roll pin it's about 133 thousandths I'd say that would be 8 thousandths over 1/8th inch, So I say 1/8th inch would be close enough!!!! 3 MM?? You sure it wasn't a 3.5 or 4 MM,a 3 mm would be to loose!!

 

[rascal_rascal_99]

Yep, you have it right,or at least close enough!! I just Mic'd a roll pin it's about 133 thousandths I'd say that would be 8 thousandths over 1/8th inch, So I say 1/8th inch would be close enough!!!! 3 MM?? You sure it wasn't a 3.5 or 4 MM,a 3 mm would be to loose!!

Actually now that you mention it, I think there was a .5 on the end of it...must have been a 3.5. I'm quite sure it wasn't loose, I remember squeezing one end down just a little to help get it started easier and then hammering it in.

Make sure to pay good attention cleaning everything out good around the gear/bushing area to clean out all of the teeth and threads on the gears from all the old bushing dust that will be in there. It really is a pretty simple job to do.

 

[onedef92]

Be sure and coat the headlight motor gear with plenty of white lithium grease, too, to ensure years of trouble-free operation.

 

[Trav]

My only headlight motor problem...

I had the dreaded spin-on after hitting the switch. At one point the headlight stopped halfway and the worst shrieking I've ever heard came from the motor. Stationed in Germany with no Chevy dealer anywhere close, I figured I had nothing to lose by pulling the assembly myself. About 6 or 8 bolts and one connector later, I had it in my kitchen. I took apart the motor casing (two halves) and discovered that corrosion had made its way into the motor. The rust had formed under the glue that held the magnets into the motor armature assembly. The magnets came unglued and "stuck" to the armature as it spun to operate the headlights; hence the shrieking. I wirebrushed the mounting spots in the assembly, used some JB Weld on the magnets and glued them back into place. I wedged something in there to hold them in place (can't remember what) and let it dry overnight. Next day, I reassembled the motor (with a bead of RTV silcone on the casing) and it hasn't been a problem since. That was 9 years ago.

By the way, if your motor fails... unplug the motor (you can leave the other one hooked up!) and you can manually rotate the headlight into any position and lock it with the little wire that goes around the spin knob. Poke around, you'll see them. Your wrist will get sore, but it works perfectly.

Good luck.... Trav

 

[onedef92]

It takes me about a hour a side by myself,but I've done it at least 100+ times!! Be careful and soak all the bolts and screws with PB Blaster!! If you break one off, then it becomes a Real PITA!!:L:L:L

True. And if you lose that little BB-sized bearing on the tip of the commutator shaft, your ass is pretty much hosed, too...;help


Again, a dab of white lithium grease is your best friend when it comes to a C4 Corvette headlight motor overhaul.

 

[kj5zv]

Bearings

Found some at Lowe's. If I remember right, about $2.00 for two. When installing them found that they were just slightly to large, few strokes with a file and while it is a slightly tight fit. worked very well. Installed this in June and not a bit of trouble with the headlight after that. Hope that helps.